Recently, demand for IoT technology has increased and narrowband IoT (NB-IoT) technology has been discussed in order to support such an IoT service. NB-IoT seeks to provide appropriate throughput between connected apparatuses despite low apparatus complexity and low power consumption.
In 3GPP of the NB-IoT standards, NB-IoT technology capable of being combined with other 3GPP technologies such as GSM, WCDMA or LTE has been studied. To this end, a resource structure which will be used from the viewpoint of a legacy system has been discussed.
FIG. 1 is a diagram illustrating three modes which may be used in NB-IoT.
In order to satisfy the above-described demand, in NB-IoT, a channel bandwidth of 180 kHz is being considered for use both on uplink and downlink, which corresponds to one physical resource block (PRB) in an LTE system.
As shown in FIG. 1, NB-IoT may support three modes such as standalone operation, guard band operation and inband operation. In particular, in the inband mode shown in the lower side of FIG. 1, NB-IoT operation may be performed through a specific narrowband in an LTE channel bandwidth.
In addition, in NB-IoT, using an extended DRX cycle, half-duplex FDD (HD FDD) operation and a single receive antenna in a wireless apparatus substantially reduce power and cost.